Survival, Growth and Reproduction of Cryopreserved Larvae from a Marine Invertebrate, the Pacific Oyster (Crassostrea gigas)

This study is the first demonstration of successful post-thawing development to reproduction stage of diploid cryopreserved larvae in an aquatic invertebrate. Survival, growth and reproductive performances were studied in juvenile and adult Pacific oysters grown from cryopreserved embryos. Cryopreservation was performed at three early stages: trochophore (13 +/- 2 hours post fertilization: hpf), early D-larvae (24 +/- 2 hpf) and late D-larvae (43 +/- 2 hpf). From the beginning (88 days) at the end of the ongrowing phase (195 days), no mortality was recorded and mean body weights did not differ between the thawed oysters and the control. At the end of the growing-out phase (982 days), survival of the oysters cryopreserved at 13 +/- 2 hpf and at 43 +/- 2 hpf was significantly higher (P<0.001) than those of the control (non cryopreserved larvae). Only the batches cryopreserved at 24 +/- 2 hpf showed lower survival than the control. Reproductive integrity of the mature oysters, formely cryopreserved at 13 +/- 2 hpf and 24 +/- 2 hpf, was estimated by the sperm movement and the larval development of their offspring in 13 crosses gamete pools (five males and five females in each pool). In all but two crosses out of 13 tested (P<0.001), development rates of the offspring were not significantly different between frozen and unfrozen parents. In all, the growth and reproductive performances of oysters formerly cryopreserved at larval stages are close to those of controls. Furthermore, these performances did not differ between the three initial larval stages of cryopreservation. The utility of larvae cryopreservation is discussed and compared with the cryopreservation of gametes as a technique for selection programs and shellfish cryobanking

Cryopreservation of Pacific oyster (Crassostrea gigas) larvae: Revisiting the practical limitations and scaling up the procedure for application to hatchery

International audiencePacific oyster Crassostrea gigas is one major species for aquaculture, and the development of breeding programs and the need for preservation of wild stock genetic resources prompted the need for larvae cryopreservation. The objective of the present study was to choose the most reliable protocol from several existing publications, to test its biological and practical limitations, and to adapt it to hatchery conditions. The selected protocol was characterized by a very slow freezing rate without seeding, and by the use of ethylene glycol and sucrose as cryoprotectant. The best survivals after thawing and rearing up to 48 h post fertilization (hpf) were obtained with larvae that were frozen at late trochophore (20 hpf) and early-D (24 hpf) stages. Increasing the larvae concentration in the straws and using high throughput straw filling and freezing devices did not alter the cryopreservation outcome. The whole procedure was applied to cryopreservation in a commercial hatchery (Satmar, France), and the thawed larvae yielded 9.4 ± 4.5% survivals at 12 days post fertilization. The overall success was dampened by some variability in the larvae survival that is likely due to the physiological status of the larvae. In all, the proposed procedure is robust and reliable and can be used for cryobanking of oyster genetic resources

Increased plasma-immune cytokines throughout the high-dose melphalan-induced lymphodepletion in patients with multiple myeloma: a window for adoptive immunotherapy.

International audienceHigh-dose melphalan (HDM) followed by autologous stem cell transplantation (ASCT) is a standard treatment for patients with multiple myeloma. However, lymphocyte reconstitution is impaired after HDM. Recent work has suggested that the lymphopenia period occurring after various immunosuppressive or chemotherapy treatments may provide an interesting opportunity for adoptive antitumor immunotherapy. The objective of this study was to determine an immunotherapy window after HDM and ASCT, evaluating T cell lymphopenia, and measuring circulating immune cytokine concentrations in patients with multiple myeloma. The counts of T cell subpopulations reached a nadir at day 8 post-ASCT (day 10 post-HDM) and recovered by day 30. IL-6, IL-7, and IL-15 plasma levels increased on a median day 8 post-ASCT, respectively, 35-fold, 8-fold, and 10-fold compared with pre-HDM levels (p < or = 0.05). The increases in IL-7 and IL-15 levels were inversely correlated to the absolute lymphocyte count, unlike monocyte or myeloid counts. Furthermore, we have shown that CD3 T cells present in the ASC graft are activated, die rapidly when they are cultured without cytokine in vitro, and that addition of IL-7 or IL-15 could induce their survival and proliferation. In conclusion, the early lymphodepletion period, occurring 4-11 d post-HDM and ASCT, is associated with an increase of circulating immune cytokines and could be an optimal window to enhance the survival and proliferation of polyclonal T cells present in the ASC autograft and also of specific antimyeloma T cells previously expanded in vitro

Cost-effectiveness of Pegfilgrastim versus Filgrastim after high-dose chemotherapy and autologous stem cell transplantation in patients with lymphoma and myeloma

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Cost-effectiveness of Pegfilgrastim versus Filgrastim after high-dose chemotherapy and autologous stem cell transplantation in patients with lymphoma and myeloma

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Factors influencing extramedullary relapse after allogeneic transplantation for multiple myeloma

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Low doses of GM-CSF (molgramostim) and G-CSF (filgrastim) after cyclophosphamide (4 g/m2) enhance the peripheral blood progenitor cell harvest: results of two randomized studies including 120 patients.

International audienceThe use of a combination of G-CSF and GM-CSF versus G-CSF alone, after cyclophosphamide (4 g/m2) was compared in two randomized phase III studies, including 120 patients. In study A, 60 patients received 5 x 2 microg/kg/day of G-CSF and GM-CSF compared to 5 mug/kg/day of G-CSF. In study B, 60 patients received 2.5 x 2 microg/kg/day G-CSF and GM-CSF compared to G-CSF alone (5 microg/kg/day). With the aim to collect at least 5 x 10(6)/kg CD34 cells in a maximum of three large volume leukapherises (LK), 123 LK were performed in study A, showing a significantly higher number of patients reaching 10 x 10(6)/kg CD34 cells (21/29 in G+GM-CSF arm vs 11/27 in G-CSF arm, P=0.00006). In study B, 109 LK were performed, with similar results (10/27 vs 15/26, P=0.003). In both the study, the total harvest of CD34 cells/kg was twofold higher in G-CSF plus GM-CSF group (18.3 x 10(6) in study A and 15.85 x 10(6) in study B) than in G-CSF group (9 x 10(6) in study A and 8.1 x 10(6) in study B), a significant difference only seen in multiple myeloma, with no significant difference in terms of mobilized myeloma cells between G-CSF and GM-CSF groups